This invention relates to a fluid product dispenser comprising a reservoir with a volume that can be varied by displacement of a mobile wall in order to reduce the volume of the reservoir and a distribution orifice. The mobile wall may be moved either by means of a deformation or a sealed slide. In the first case, the reservoir or at least part of the reservoir is deformed, which is why a deformable and/or elastic flexible material is used, and in the second case piston-follower systems are used in which a piston moves inside a cylindrical barrel in order to gradually reduce the useful volume of the reservoir. In both cases, the volume of the reservoir reduces as the fluid product is extracted from it. The fluid product is thus never in contact with air inside the reservoir, which improves conservation of the product, particularly when it is sensitive to oxidation or deterioration in contact with air.
Examples of dispensers with a deformable reservoir include dispensers in which the deformation is made by manual compression, that are called xe2x80x9csqueeze bottlesxe2x80x9d. The user""s hand compresses the reservoir directly. On the other hand in piston-follower systems, the piston-follower rises in the receptacle either automatically under the effect of the negative pressure created in the receptacle when the dispenser is activated, or by means of a spring that pushes the piston so that the internal volume of the receptacle is reduced.
The purpose of this invention is to overcome the above mentioned disadvantages with prior art by proposing a dispenser provided with actuation means that act on the mobile wall of the dispenser.
The European application EP-0 869 080 describes a dispenser comprising an helical bellows. The outer wall of the bellows forming the helical thread engages a rotative skirt provided with an inner annular rib. So, the free rotation of the skirt causes the helical threads to be progressively gathered in the manner of an accordion.
The single annular rib of the skirt is located at the top of the bellows, so that the rib initially engages the uppermost thread of the bellows and engages progressively the below threads as the skirt is rotated. The threads of the bellows have to be both flexible to allow the gathering of the bellows and rigid to permit the threaded engagement with the annular rib of the skirt. However, the bottom of the bellows is free and has therefore to be also rigid. Such a bellows is not easy to manufacture, since it has to be both flexible and rigid.
The present invention overcomes all these drawbacks in defining a simpler dispenser.
In this purpose, actuation means are rotary and comprise a thread that is engaged with the reservoir. Several distinct threads may be provided. Advantageously, the reservoir comprises one or several displacement flanges fixed to the mobile wall and that engage in the thread. Thus, by rotation of the actuation means, the mobile wall moves in translation and tends to reduce the useful volume of the reservoir. It is to be noticed that the actuation means directly acts on the bottom of the reservoir, whereas in the previously commented European application, the bottom of the reservoir is pulled and not pushed.
According to one embodiment, the dispenser comprises a body, the rotating actuation means being fitted free to rotate in the said body without making any translation displacement with respect to the said body. The actuation means thus turn freely in the body forcing the mobile wall upwards to reduce the volume of the reservoir. Advantageously, the body forms a part of the reservoir.
According to one characteristic of the invention, the reservoir comprises bellows in a leak tight contact with the body, the said bellows forming the mobile wall. Advantageously, the bellows comprises a leak tight attachment collar connected with a connection sleeve formed by the body. Thus, the bellows is fixed firstly to the body and secondly is engaged by threading with actuation means. According to one practical embodiment, the mobile wall is connected to the attachment collar through a deformable wall. The distribution orifice may also be formed in the body.
According to another aspect of the invention, the actuation means form a bottom for the dispenser.
According to another characteristic, the actuation means comprise a peripheral gripping device capable of moving the actuation means in free rotation in the body. Thus, the body can be held in place with one hand and the actuation means can be rotated with the other hand.